中国科学院昆明动物研究所机构知识库

食物资源和人为干扰会影响越冬水鸟的觅食地选择和觅食行为，越冬水鸟觅食生境会受剧烈的周期性水文波动或气象因素影响而产生大范围的变动。随着湿地生境不断受到人类活动的影响，一些由人为活动造成的次生生境已经开始被越冬水鸟利用，并成为其响应湿地退化及应对人类活动干扰的重要手段。因此，本研究拟通过研究纳帕海人为改造生境猪拱地对黑颈鹤觅食生境选择的影响，探讨人为改造生境对越冬水鸟觅食的重要作用和意义。2016年~2017年我们在云南省香格里拉市纳帕海自然保护区，对越冬黑颈鹤（Grus nigricollis）的觅食生境选择及觅食行为做了详细调查，观察了黑颈鹤在由人类放牧家猪而产生的次生生境猪拱地上的取食活动，并与纳帕海其他两种黑颈鹤主要觅食生境，草地和浅水沼泽进行了对比，分析了三种不同类型觅食生境的面积、分布、生境的可获取性、黑颈鹤对它们的利用率、偏好的变化及在不同觅食生境中黑颈鹤取食行为的差异。纳帕海黑颈鹤觅食生境会随越冬期推移而不断变化。从越冬前期至越冬后期，草地的分布面积分别为409hm2、1237hm2、1782hm2，约占同期可供黑颈鹤利用觅食生境总面积的54%、67%、70%；浅水沼泽的分布面积分别为111hm2、45hm2、148hm2，约占同期可供黑颈鹤利用觅食生境总面积的15%、3%、6%；人造次生生境猪拱地的分布面积分别为228hm2、155hm2、74hm2，约占同期可供黑颈鹤利用觅食生境总面积的30%、12%、3%。纳帕海黑颈鹤觅食生境的可获取性随越冬期不断变化，黑颈鹤对不同觅食生境表现出不同偏好。在三种觅食生境中，草地的可获取性最高，但黑颈鹤对其利用率在越冬期会逐渐下降，从越冬前期的40%~50%持续下降到15%~20%，在越冬后期回升至15%~30%，并一直表现出回避状态；浅水沼泽在所有生境中的可获取性最低，但黑颈鹤对其拥有最稳定的利用率，在整个越冬期维持在30%~50%，并一直表现出偏好状态；猪拱地的可获取性在越冬期呈持续下降趋势，黑颈鹤对其利用率却先升高后降低，分别为20%~25%、35%~50%、35%~40%，黑颈鹤在越冬前期对猪拱地为无明偏好，但在越冬中期至越冬后期表现出偏好状态。黑颈鹤在三种觅食生境中的觅食活动具有较大差异。黑颈鹤在草地上的取食总时间、单次取食动作持续时长均低于在猪拱地和浅水沼泽中（P＜0.05），警戒时间和搜索食物用时高于其他两种生境（P＜0.05）；而猪拱地与浅水沼泽的差异在越冬前期和越冬后期不显著（P＞0.05），但在越冬中期，黑颈鹤在猪拱地上的搜索食物用时会低于浅水沼泽（P＜0.05）。根据研究结果，提出以下保护建议：重点保护浅水沼泽生境，越冬前期禁止放养家猪，越冬中后期可以在严格控制数量的情况下适当放养家猪。

The foraging behavior and selection of foraging location of wintering water birds are affected by food resources and human behavior. Meteorological factors and periodical hydrological fluctuations would also bring wide range of changes onto wintering water birds foraging habitat. For coordinating with the increasing rang of human activities in wetland habitat, some wintering water birds have already adapted to make use of the secondary habitat caused by human behavior, and this adaption is also a very significant respond of wetland degradation and human behavior for wintering water birds.During the winter of 2016 to 2017, we made a detailed investigation on wintering black-necked crane regarding their foraging behavior and selection of foraging location in Napahai Nature Reserve in Shangri-La of Yunnan province. The investigation was especially covered of the foraging behavior on pig-feed area, which is a secondary habitat caused by pigs herding. The comparison group was other two types of black-necked cranes who respectively take grassland and shallow swamps as their foraging habitat. We analyzed the distribution and availability of three different types of foraging habitat, and the usage, preference and foraging behavior difference of black-necked cranes regarding the different habitat.The distribution of foraging habitat of Napahai black-necked crane would have constantly change regarding passing of winter period. During winter period, the area of the grassland distribution has been recorded as 409hm2, 1237hm2, 1782hm2; basically, they were taking over the total area of available foraging habitat for black-necked cranes of 15%, 3%, 6% of the corresponding period. The area of the pig-feed area distribution was recorded as 228hm2, 155hm2, 74hm2, took over the total area of 30%, 12%, 3%.In the three types of habitat, grassland achieves the highest availability. However black-necked crane would have a decreasing usage regarding time passing, from 40%~50% to 15%~20% in the early stage of winter period, in later stage of winter it will rise to 15%~30% and cranes would also have a trend of avoiding to grassland habitat. The shallow swamps have the lowest availability, but cranes have a most stable usage of them. The usage of shallow swamps maintains around 30% to 50% in the entire winter period, and cranes showed a continuous preference. Pig-feed area showed a decreasing trend in winter period. The usage increases in early stage and fall down after. In three periods the usages respectively are 20%~25%, 35%~50%, 35%~40%. Black-necked crane has a randomly use of ping-feed area without an obvious preference in early stage of winter. However, in medium and late stage cranes would have preference on ping-feed area. Black-necked crane also showed difference in foraging behavior in three types of habitats. We split foraging behavior into sentinel behavior and feeding behavior, and split feeding behavior into searching stage and swallowing stage. The result showed that total feeding time, and average single feeding time of black-necked crane in grassland are all shorter than in pig-feed area and shallow swamps (P<0.05). The time cost of sentinel behavior and searching stage are all significantly longer than in other two habitats (P<0.05). In ping-feed area and shallow swamps, the time difference in early and late stages of winter was not quite significant (P>0.05). However, in the medium sage of winter, the time of searching stage in pig-feed area would be shorter than in shallow swamps (P<0.05). According to the results, protection suggestions were proposed as follow: Protect the marsh wetland area. Bans on pig husbandry in early in wintering period. Control the time and intensity of pig husbandry in middle and later wintering periods.